433Re: Wish List
- Apr 17, 2009Dave,
Thanks for the intervention!
Honestly I had the impression that it was an H-thing but never got the curiosity (until now) to see PA3AKE's site and have a good read on this.
You sure made me start reading the H-Mode mixer documents and try to find the differences with your design.
Next time I have to be more careful. :-)
By the way are the production boards ready to order?
--- In email@example.com, Dave - WB6DHW <brainerd@...> wrote:
> The UHFSDR does not use an H mode mixer(at least if I understand what
> an H mode mixer is). The UHFSDR uses 2 standard double balanced mixers.
> The DBM's have about 6 dB of loss verses 1dB or less for the QSD.
> But, DBM's are available for frequencies well into the tens of GHz. It
> uses a quadrature LO as do all the other SDR's.
> Dave - WB6DHW
> Christos Nikolaou wrote:
> > Hi Joe,
> > The UHFSDR kit is still sitting there in pieces in my lab pipeline...
> > I envy that you already got the feeling of it and how the H-Mode mixer works in comparisson to the QSD/QSE we were familiar with.
> > I didnt go into the trouble of building it on the beta board and patiently waiting Dave to anounce the new rectified boards.
> > Appart from the first touches on PowerSDR-IQ for UHFSDR usage I didnt had the time to incorporate the requests done so far yet. But I will, since I also want to have the H-Mode mixer experience and SDR up to UHF.
> > Although you had your Easter last week, its the Orthodox Easter here so you have my Season Greetings.
> > 73,
> > Christos SV1EIA
> > --- In firstname.lastname@example.org, "joe price" <joeprice@> wrote:
> >> Christos,
> >> I have had some success with Dave's WB6DHW's UHFSDR project on two meters. would you please consider the following changes to your next revision.
> >> Add the 2 meter band selection box in the Band-HF under the S meter.
> >> Keep the extended frequency box checked under General Si570 (to allow TX on 2).
> >> Store TX/RX I/Q image data for 2 meters.
> >> Enable the TX Sequencing time so that it's used in both directions not
> >> just RX to TX. The UHFSDR board has a small transient switching from TX to RX
> >> which activates the RX AGC when TIME is set to slow (SSB) Fast AGC is OK.
> >> Joe wa9cgz
> >> .
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